The present invention relates to a testing apparatus for examining a semiconductor wafer, and more particularly, to a testing apparatus for such use, the apparatus including a probe card holder unit whereby the probe card is softly mounted on the apparatus under air suction, without the use of any mechanical means, such as a plug and a jack.
In the manufacture of microelectronic devices including semiconductor wafer chips, the wafer chips must be tested prior to the application of terminal leads to them in order to ascertain if they function properly and reliably as end products. For such tests a tester including a probe card is employed, wherein the probe card is secured to a holder. The probe card includes a number of radially arranged probe needles, which are intended as terminal leads for testing purpose. A problem is involved in fixing the probe card to the holder with the use of conventional plugs and jacks through which the electrical connections are also made between the probe needles and an outer testing electric circuit. The number of the plugs and jacks, of course, corresponds to that of the probe needles on the probe card, and an increase in the number thereof increases the burden of fixing and detaching the probe card to and from the holder. Nevertheless, it was not a serious problem when the degree of circuit integration in the electronic devices was low and not so complex as that of the most recent ultra large LSIs. The recently developed microelectronic devices include commonly-called ultra LSIs or super LSIs, and the terminals thereof have tremendously increased in number, such as more than 200. Accordingly, the probe card must have a corresponding number of probe needles, which requires an increased number of plugs and jacks. This increases the toil of connecting the probe card to the testing device. Particularly, the problem is that a relatively large force must be imparted to the probe card so as to enable it to be connected to and disconnected from, the holder. As a result, it frequently happens that the probe card is broken or damaged.